1. Field of the Invention
The present invention relates to a vehicle for cargo handling such as a forklift or bulldozer, especially those equipped with a theft prevention mode and an emergency operating mode where at least the traveling capability of the vehicle is restricted while theft of the vehicle is prevented in the event of an emergency such as earthquake and fire.
2. Description of the Related Art
A vehicle for cargo handling such as a forklift or bulldozer is used in particular areas such as a factory or construction site and usually transported to a destination on a truck and it requires a special license to drive those vehicle, so there was little worry about theft of the vehicle even with the key attached. Moreover, it was common to leave the key in as a number of drivers usually take turn to drive this type of vehicle and as for a forklift, a driver who delivers cargos on his truck uses a forklift to unload the cargos at night.
However, recently theft of the cargo handling vehicles from factories or construction sites became noticeable. The vehicle is stolen on a truck and is used to destroy a building or equipment that is normally unbreakable. Thus, it is urgently needed to provide a theft prevention mode for the cargo handling vehicles.
Patent Reference 1 (JP64-46329A) discloses an electronic device to be loaded on a vehicle with a theft prevention function. The electronic device is equipped with a theft prevention mechanism having a normal operating mode wherein a normal operation of the vehicle is allowed in a state that the device is loaded in the vehicle, and a theft prevention mode wherein the normal operation of the vehicle is prohibited when the device is removed from the vehicle.
Moreover, for a forklift, vehicle characteristics such as operation of levers and response characteristics to operation amount and speed of levers and the like can be arbitrarily set for each driver. However, in the case of more than one operator driving the forklift, each operator has to reset vehicle characteristics every time. Patent Reference 2 (JP2003-63798A) provides an industrial vehicle in which each operator can input a password and operation of the forklift is allowed only when the password matches, and then vehicle characteristics corresponding to the entered password, is retrieved from a memory unit for solely storing characteristic data so as to operate the forklift according to the retrieved characteristic that matches the entered password.
As for a hydraulic shovel, a password is required to operate the vehicle and a monitor for password entry is also used for displaying information such as operation conditions. However, the monitor is installed inside an operator's room and activation of the monitor requires password entry and when changing the settings, password entry is required for each change, which increases workload for the operator. Therefore, Patent Reference 3 (JP2007-76455A) shows an operation vehicle equipped with a theft prevention device wherein when the power is on but the engine is still off, the information of the vehicle can be displayed on the display device without entering the password.
As described above, it is already known to use a password for theft prevention in vehicles such as a vehicle loaded with the electronic device (Patent Reference 1), industrial vehicle (Patent Reference 2) and the operation vehicle (Patent Reference 3), and especially a cargo-handling vehicle being operated by more than one operator. However, when the cargo-handling vehicle is parked in middle of the street for instance and the operator temporarily leaves the site, the vehicle cannot be moved without password entry although the key is in and this can cause an obstruction to other drivers. Also in the case of emergency such as earthquake or fire, the vehicle cannot be moved without password entry.
In view of this, an object of the present invention is to provide a cargo-handling vehicle such as forklift or a bulldozer which is operated by more than one operator, wherein limited operation of the vehicle such as moving the vehicle is allowed in the event of an emergency while theft of the vehicle is prevented even when the key is left in the vehicle.